Field of the Technology
The invention relates to the field of methods or apparatus specially adapted for installing, maintaining, repairing, or dismantling electric cables or lines, IPC H02G1/02 for overhead lines or cables and IPC B08B1/04 for cleaning by methods involving the use of tools, brushes, or analogous members using rotary operative members.
Description of the Prior Art
Overhead power lines are used to carry current across great distances and interconnect the electric grid between major cities, power stations and remote towns. These lines typically are made from aluminum alloys and carry currents upwards of 1000 kV. Typically, overhead power lines are not insulated to reduce the operational cost of power transmission for large quantities of electric energy. Instead, overhead powerlines are instead insulated by free air. Although aluminum naturally creates a protective oxidized layer, this layer can grow increasingly thick, or there can be a buildup of particles such as airborne salt, ash, minerals deposited by rain, and bird droppings. As material adheres to the power line, the impedance of the line increases and results in power being dissipated from the lines in the form of heat.
The U.S. Energy Information Administration (EIA) estimates that roughly 5% of all electricity entering overhead power lines is lost as a result transmission. The global average is roughly 10%, but in countries such with power lines in states of disrepair, such as India, power losses can exceed 25%. These power losses translate to about 70 TJ of dissipated energy every year for the US alone. The annual dissipated energy is valued at around 2 billion dollars.
To keep sediment from perpetually accumulating on the overhead power lines, utility companies have addressed this issue and regularly clean these power lines of any build ups. There are several problems that arise from the need to regularly scrub power lines. Ground based transmission line cleaning is either dangerous or expensive. If the lines are left live during cleaning, the cleaning crew is exposed to the danger of arcing between the ground and the transmission lines, resulting in short circuits and fatalities. If the lines are disconnected for cleaning, the utility companies looses revenue in the form of lost power sales. Additionally, many transmission lines are inaccessible by ground crews due to the topography through which they run. Many transmission lines run through mountains, dense forests, and in generally remote hard to access areas.
U.S. Pat. No. 4,477,289 METHOD FOR WASHING VOLTAGE TRANSMISSION LINE INSULATORS outlines a method for using pressurized water cannons shot from helicopters that addresses the issues of remote access. Helicopter assisted washing addresses the issues ground crews face, but is still costly as it requires specialized labor and the use of specialty helicopters that have been fitted with the equipment necessary.
Chinese Application CN201620110090 discloses an automatic solar powered cleaning device of transmission lines, which rides on the transmission line and cleans the line unattended using a plurality of motor driven brushes to scrape or brush the line clean around its entire circumference.